Children are not substantially contributing to the spread of Covid-19 in their household or in schools, the health watchdog has said.

The Health Information and Quality Authority (Hiqa) has published summaries investigating the international evidence on immunity and the spread of the virus by children.

It said that, while evidence is limited, children are not significant contributors to the spread.

Hiqa deputy chief executive and director of health technology assessment Dr Mairin Ryan said: “One study suggests that, while there is high transmission of Covid-19 among adults aged 25 years or older, transmission is lower in younger people, particularly in those under 14 years of age.

“An Australian study that examined potential spread from 18 confirmed (nine students and nine staff) cases to over 800 close contacts in 15 different schools found that no teacher or staff member contracted Covid-19 from any of the initial school cases.

“One child from a primary school and one child from a high school may have contracted Covid-19 from the initial cases at their schools.”

Hiqa also found that there remains a lack of clear evidence as to whether long-term immunity is possible from Sars-CoV-2 (the virus that causes Covid-19).

Dr Ryan said studies have shown that antibodies against Sars-CoV-2 develop soon after infection.

“However, as Sars-CoV-2 is a new virus, there is no long-term evidence of immunity. Continued monitoring is needed to assess the adequacy and duration of the immune response for Covid-19,” she said.

“Evidence for other types of serious coronavirus infections, such as Sars-CoV-1, shows that the antibody response is maintained for one to two years after initial infection and decreases thereafter.

“It is not yet possible to determine if reinfection is possible following recovery from Covid-19. While some individuals have tested positive after recovery, this is likely due to virus re-detection where there is intermittent shedding of the virus rather than reinfection with a second virus.”